Have had our first travel trailer for 5 mos and just went on 1st non hookup trip, 4 nights. We have two 12v group 24 batteries which I charged for about 24 hrs before leaving. Since it was colder at Lake Tahoe at 6500' than normal, we had weather in the 40-50's daytime and right at freezing each night. We ran the heater for 10-15 min before bed and thru-out the night at the same rate. When we checked the batteries on the monitor the next morning, we were down to 1/3. I charged daily with Honda EU 2000, at 8 amps for up to 4 hrs per day for rest of the weekend and we really conserved our usage, mainly for water pump, furnace, one light at a time, water heater. Even made perc coffee.
I want to do an inventory of what each thing we have in the trailer uses for 12v amps, but not sure how to apply the numbers I find? Besides the amps per hour ratings, do I need to add lot more for coming on and off like water heater (electric start for gas), or furnace where it came on for 10 min every hour or so. What are the hidden things you have to add or the inefficiencies of the converter, charger, generator?
Just seems like our 140-170 amp hours should not have depleted so much each day. We have 3 stage converter, two small slides which I put in or out with truck hooked up and running, Electric jack but also use only with truck running.
The current consumed by spark generators for furnace, etc are negligible compared to current consuming devices (lights, 12 appliances, inverter, etc) and can be ignored. If you want to get really exact, you can measure each load with a meter, but keep in mind not all things will be on for the same amount of time and at the same time.
2007 Dutchman Express 31 Class C
2006 Centurion Elite V C4, Air Warrior
A Trimetric 2020 battery monitor will tell you exactly whats being pulled out of the battery in real time. Ive gone around the camper turning things on and off while looking at it to know where the 'power pigs' are.
Also, 140-170 amp hours? Is that total? If so, you really only have about half of that since you never want to take your batteries down more then half way...
My furnace will really suck my battery down overnight so I turn set point down to 50 at night and get under my down comforter. I also adjusted my thermostat to it doesn't come on as often - i.e. bigger temp increase when does comes on.
Are the batteries in good condition. If not you won't be able to charge them up fully.
You said you charge the at 8 amps. Is that 12 volts to the battery. You should be able to charge them at a C/10 rate during bulk charging or 14 to 17 amps.
You mention a monitor. Are you talking about a Link 10 or Trimetric type.
You might consider a small catalytic heater to cut down on the furnace cycling.
You could also turn the water heater off at night if it is using much current to start.
Batteries have lowered capacity in cold environments. It also sounds like you were recharging them long enough from the generator. 8 Amps X 4 hours = 32 amphours. It would have to run over 17 hours if they were depleted. Your converter could probably do a higher rate.
To measure actual consumption, you might try the fuse block. Remove the fuse for the circuit you want to measure and connect an ampmeter in place of the fuse. Do this on each circuit. Be sure to use an ampmeter with sufficient range so it does not get damaged.
This is what you should have used to charge the battery not the 12 volt generator output. The converter probably charges with 45 to 70 amps.
8 amps x 4 hours is only 32 amp/hrs per day replaced. Also you need to have econo throttle off to even get 8 amps. Anyway, plug the RV in direct and let the converter do the charging.
The furnace takes 7 to 10 amps from the battery to operate when the blower is on. I put the thermostat down to 55/60 at night and pack on the blankets.
It would be a good idea to spend $20 on a digital volt meter from sears or your local hardware store to monitor charging voltage and better monitor voltage as the battery is depleted.
A battery monitor is great and will greatly improve the energy management. However it does not provide more power. I use a digital volt meter or the wall indicator to know when to turn on the generator and an amp meter to tell when to turn it off.
2001 F150 SuperCrew 5.4 Lariat Offroad 4x4 Tow Package 4.10 Truetrac
2006 Keystone Springdale 249FWBHLS
12K SuperGlide, KGE3000Ti 2.3kw rated 2.6kw max
Frank's voltage booster, Prosine 1800 powered by 4 GC2 batteries
FYI, this is what the devices in my 20003 Cougar drew. I think most of the current generation devices are similar to this. I assumed about a 50% duty cycle for the fridge. I don't think a clamp-on dc ammeter will give highly accurate readings. If you're at all inclined to install a full-time ammeter, I highly recommend it. Besides measuring loads, it lets you know what the converter is doing, and lets you easily see if something you don't know about is turned on.
DC LOADS (amps)
static 0.1 (propane detector)
refrig 0.36 gas valve on, 0.1 idle auto, 0.05 idle gas only
water pump 4-6
bright double light 2.6
single amber light 1.2
2x scare lights 4.2
outside single light 1.2
range hood fan 1.7
range hood light 1.0
bath fan 1.4
maxxFan 1.4 / 2.3 / 3.7
heater 6.5-7
radio ~1.0A radio or CD on, 0.05A off with ignition on, nil with ignition off
tank heaters 12A (specs., not measured)
water heater, on gas, electronics 0.3, gas valve 0.5. No draw unless thermostat triggered.
landing gear 15A extend, 8A retract
slide extension 14A extend, 14A retract, >20A stalled
Offline
